Update to the 20170926 snapshot of GCC 5.4.1.

The patches to gcc/auto-profile.c and gcc/graphite-isl-ast-to-gimple.c
that were part of files/patch-libc++ have now been backported upstream
into this snapshot (in similar form) and thus can (and need to) be
removed.

lang/gcc5-devel/Makefile

@@ -2,7 +2,7 @@
 # $FreeBSD$
 
 PORTNAME=	gcc
-PORTVERSION=	5.4.1.s20170919
+PORTVERSION=	5.4.1.s20170926
 CATEGORIES=	lang
 MASTER_SITES=	GCC/snapshots/${DIST_VERSION}
 PKGNAMESUFFIX=	${SUFFIX}-devel

lang/gcc5-devel/distinfo

@@ -1,3 +1,3 @@
-TIMESTAMP = 1506026745
+TIMESTAMP = 1506528342
-SHA256 (gcc-5-20170919.tar.xz) = d9ab03070d695eed0ab946e2e574d96aa3a3b6cd82c4a4470c4f427e23bb9cad
+SHA256 (gcc-5-20170926.tar.xz) = dfa5537341d7efb44f0ce0db93c95012d4d34c9a1fdbbc2f4ddde582cc85ece3
-SIZE (gcc-5-20170919.tar.xz) = 69384604
+SIZE (gcc-5-20170926.tar.xz) = 69385412

lang/gcc5-devel/files/patch-libc++

@@ -1,36 +1,3 @@
---- gcc/auto-profile.c.orig	2015-01-18 02:25:42 UTC
-+++ gcc/auto-profile.c
-@@ -19,11 +19,9 @@ along with GCC; see the file COPYING3.  
- <http://www.gnu.org/licenses/>.  */
- 
- #include "config.h"
--#include "system.h"
--
--#include <string.h>
- #include <map>
- #include <set>
-+#include "system.h"
- 
- #include "coretypes.h"
- #include "hash-set.h"
---- gcc/graphite-isl-ast-to-gimple.c.orig	2017-01-19 21:02:12 UTC
-+++ gcc/graphite-isl-ast-to-gimple.c
-@@ -38,6 +38,7 @@ extern "C" {
- #endif
- #endif
- 
-+#include <map>
- #include "system.h"
- #include "coretypes.h"
- #include "hash-set.h"
-@@ -75,7 +76,6 @@ extern "C" {
- #include "tree-scalar-evolution.h"
- #include "gimple-ssa.h"
- #include "tree-into-ssa.h"
--#include <map>
- 
- #ifdef HAVE_isl
- #include "graphite-poly.h"
 --- gcc/system.h.orig	2015-01-05 12:33:28 UTC
 +++ gcc/system.h
 @@ -217,6 +217,7 @@ extern int errno;